OBJECTIVETo investigate the therapeutic effect of infrared radiation (IR) on the skin scald in rats.

METHODSThirty-nine male Wistar rats were used in the study, and they were randomly divided into normal control (C, n = 13), scald (S, n = 13, no treatment after scalding) and treatment (T, n = 13, with IR radiation treatment for 5 days since 2nd post scalding day (PSD) groups. The rats in S and T groups were subjected to deep partial thickness scalding on the back. The cutaneous tissue samples from rat wound in each group were harvested on the 3rd and 7th PSD for pathomorphological examination. DNA synthesis in wound tissue was analyzed by 3H-TdR incorporation method, and the vascular permeability in cutaneous tissue, degree of tissue edema and MDA content were determined by corresponding methods.

RESULTSEpidermal exfoliation, cutaneous ulcer, follicular atrophy and damage, and massive formation of collagen were identified in the skin wound of rats in S group on the 7th PSD compared with C group. The skin in T group was smooth with slight atrophy and a few collagen fibers in follicles. The 3H-TdR incorporation amount in the rats in T group (1856.33 +/- 343.81 cpm/mg) on the 7th PSD was significantly higher than that in S group (1353.95 +/- 274.48 cpm/mg) (P < 0.01). The tissue permeability, edema degree and MDA content in the cutaneous tissue in S group were obviously higher than those in group C, while these indices were markedly lower in T group when compared with those in S group (P < 0.01-0.001).

CONCLUSIONTreatment with IR seemed to be beneficial to the promotion of skin tissue metabolism and tissue repair.